28644738 has 8 divisors (see below), whose sum is σ = 57289488. Its totient is φ = 9548244.

The previous prime is 28644731. The next prime is 28644743. The reversal of 28644738 is 83744682.

It is a sphenic number, since it is the product of 3 distinct primes.

28644738 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 28644738.

It is not an unprimeable number, because it can be changed into a prime (28644731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2387056 + ... + 2387067.

It is an arithmetic number, because the mean of its divisors is an integer number (7161186).

Almost surely, 2^28644738 is an apocalyptic number.

28644738 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28644738 is a wasteful number, since it uses less digits than its factorization.

28644738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4774128.

The product of its digits is 258048, while the sum is 42.

The square root of 28644738 is about 5352.0779142311. The cubic root of 28644738 is about 305.9719526602.

The spelling of 28644738 in words is "twenty-eight million, six hundred forty-four thousand, seven hundred thirty-eight".